UKC

Hello again UKC DIY people,

Right, I can't find a definitive answer on this (maybe there isn't one), so thought I'd ask on here. We're laying a wooden floor throughout the downstairs of the house. This consists of 2-3M long planks, 2cm depth, laid on / nailed to 2 x 2" battens. Only issue is that there is a small extension to the rear of the house which has a raised concrete slab, approx 2" higher than floor throughout rest of house.

The plan is to continue the flooring beyond the battened area into the raised slab area at the same height. In theory the flooring will then be flush with the raised slab area and hey presto we will 'lose' the slab and have one floor level throughout the downstairs.

We had thought we could float the floor in this raised area but apparently this isn't possible with oak due to potential for warping / movement. So, as I understand it, the only option is an adhesive (Sika make some that sound suitable). Does this sound like the right way to go or are there are other things we should be considering?

Any help much appreciated.

In reply to ksjs: From what I have found you will always get some shinkage and expansion with an oak floor, especially in an area with a lot of light/heat.

the options you have realy are to lay a ply base then plane the planks down to keep your level, this could then be glued/secret nailed, or there is a self adhesive underlay you can use as you will need a waterproof barrier between the concrete and the wood, this holds the wood in place, I went for the self adhesive underlay but I am using engineered oak not solid so the shrinkage should be minimal

In reply to caseyfather: Well, I guess the area has a lot of heat and light as the room has French doors and gets morning sun. I hadn't thought of the ply base but I think we don't have the depth to do this? I like the self-adhesive underlay idea as it will form a vapour barrier (though I'm pretty sure there is a basic one in place) and should ensure the entire floor is secured so hopefully less scope for movement. Maybe though the wood does need to move to some extent otherwise it will split / warp? No easy answers here...

In reply to ksjs: I`m a time served joiner.... here is how I would do it...
Firstly put a plastic DPC on the concrete floor to stop any damp ingress, then lay over the flooring as normal but once its finished you will have to screw and plug the flooring down, if you pilot hole the boards slightly over size that will allow for any movement and you can get a plug cutter from B&Q to plug the screw holes so they won`t be seen.

In reply to ksjs:
I've used Sika Bond T52 (or T54, I can't remember which?). Anyway it is excellent stuff. I also tried some Screwfix stuff just to finish off a bit having run out of Sika Bond, it was rubbish.
The Sika stuff is genuinely ace, but not cheap.

In reply to Nik Jennings: You're right, something like £8 a cartridge and we need 12! Cheers for the info.

In reply to dan: Interesting - I was thinking about fixing into the concrete but wasn't sure how this could be done; would it not look a bit ****? Mind you there might not be too many plugs if we go light on the fixing, it's not a heavy traffic area so that should be OK (but is very open / obvious so dodgy fixings would be easily seen).